def check_steg(self,data):
doin = True
if not STEG_ENGINE_IS_ON:
doin = False
# LEVEL 3 : PROTOCOL FILTER
if F_NIV3 != "":
if self.type3 != PROTO3:
doin = False
# LEVEL 3 : DESTINATION ADDRESS FILTER
if F_NIV3_DST != "":
if self.type3 == "0800":
if not (steglib.check_ip(data[30:34],netlib.format_ip(F_NIV3_DST))): # ipv6 : 0x86dd, data[38:54]
doin = False
else:
doin = False
# LEVEL 3 : SOURCE ADDRESS FILTER
if F_NIV3_SRC != "":
if self.type3 == "0800":
if not (steglib.check_ip(data[26:30],netlib.format_ip(F_NIV3_SRC))): # ipv6 : 0x86dd, data[22:38]
doin = False
else:
doin = False
# LEVEL 4 : PROTOCOL FILTER
if F_NIV4 != "":
if self.type4 != PROTO4:
doin = False
return doin
def run(self):
while self.is_running:
for data in iter(self.inbuffer.get, None):
# translation d'adresses niveau 2
if self.num == 0:
data = data[:6]+netlib.format_mac(self.outMac)+data[12:] # switch MAC
elif self.num == 1:
data = netlib.format_mac(self.outMac)+data[6:] # switch MAC
# translation d'adresses niveau 3 + calcul de checksums
self.type3 = netlib.get_type3(data[12:14])
if self.type3 == "0806": # si ARP
data = netlib.arp_rewriting(data,self.outMac,self.outIp,self.num)
# optimisation : si preformat lors de init, moins de taff dans netlib
elif self.type3 == "0800": # si IPv4
ipsrc = data[26:30]
ipdst = data[30:34]
# optimisation : passer le format_ip dans l'init
if self.num == 0:
if ipsrc == netlib.format_ip(self.inIp):
ipsrc = netlib.format_ip(self.outIp)
elif self.num == 1:
if ipdst == netlib.format_ip(self.inIp):
ipdst = netlib.format_ip(self.outIp)
data = netlib.ip_rewriting(data,ipsrc,ipdst) # nat + checksum
if netlib.udp_or_tcp(data[23]): # si udp ou tcp
data = netlib.tcpudp_rewriting(data) # checksum niveau4
self.otbuffer.put(data)
return
def run(self):
while self.is_running:
for data in iter(self.inbuffer.get, None):
# translation d'adresses niveau 2
if self.num == 0:
data = data[:6] + netlib.format_mac(
self.outMac) + data[12:] # switch MAC
elif self.num == 1:
data = netlib.format_mac(
self.outMac) + data[6:] # switch MAC
# translation d'adresses niveau 3 + calcul de checksums
self.type3 = netlib.get_type3(data[12:14])
if self.type3 == "0806": # si ARP
data = netlib.arp_rewriting(data, self.outMac, self.outIp,
self.num)
# optimisation : si preformat lors de init, moins de taff dans netlib
elif self.type3 == "0800": # si IPv4
ipsrc = data[26:30]
ipdst = data[30:34]
# optimisation : passer le format_ip dans l'init
if self.num == 0:
if ipsrc == netlib.format_ip(self.inIp):
ipsrc = netlib.format_ip(self.outIp)
elif self.num == 1:
if ipdst == netlib.format_ip(self.inIp):
ipdst = netlib.format_ip(self.outIp)
data = netlib.ip_rewriting(data, ipsrc,
ipdst) # nat + checksum
if netlib.udp_or_tcp(data[23]): # si udp ou tcp
data = netlib.tcpudp_rewriting(
data) # checksum niveau4
self.otbuffer.put(data)
return
def check_steg(self, data):
doin = True
if not STEG_ENGINE_IS_ON:
doin = False
# LEVEL 3 : PROTOCOL FILTER
if F_NIV3 != "":
if self.type3 != PROTO3:
doin = False
# LEVEL 3 : DESTINATION ADDRESS FILTER
if F_NIV3_DST != "":
if self.type3 == "0800":
if not (steglib.check_ip(data[30:34],
netlib.format_ip(F_NIV3_DST))
): # ipv6 : 0x86dd, data[38:54]
doin = False
else:
doin = False
# LEVEL 3 : SOURCE ADDRESS FILTER
if F_NIV3_SRC != "":
if self.type3 == "0800":
if not (steglib.check_ip(data[26:30],
netlib.format_ip(F_NIV3_SRC))
): # ipv6 : 0x86dd, data[22:38]
doin = False
else:
doin = False
# LEVEL 4 : PROTOCOL FILTER
if F_NIV4 != "":
if self.type4 != PROTO4:
doin = False
return doin
